import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet("/postGetParameter")
public class PostGetParameterServlet extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //假设前端传过来的参数是userId=10&classId=20
        //服务器也是通过req.getParameter来获取到内容
        String userId=req.getParameter("userId");
        String classId=req.getParameter("classId");

        resp.getWriter().write("userId="+userId+",classId="+classId);
    }
}
